Wells often use screen systems in their production string to filter solid particles (e.g., sand) greater than a permitted size. Some wells are gravel packed by placing gravel in the annulus around the well screen system. For example, in an open-hole completion, gravel is typically placed between the wall of the wellbore and the production string. Alternatively, in a cased-hole completion, gravel is placed between a perforated casing string and the production string. In both types of completions, formation fluids flow from the subterranean formation into the production string through the gravel pack and well screen system.
The gravel is carried into the well with a carrier liquid in a slurry. As the gravel is placed, the liquid carrier is drained out through the well screen system to the surface.
Like reference symbols in the various drawings indicate like elements.